Does Clinical-Laboratory Workup in COVID-19 Cases Misdiagnosed as Dengue Fever in Tropical Setting or These are Two Sides of Same Coin?

Objectives: Dengue-covid-19 overlap is mixture of both diseases sharing few similarities in pulmonary and extrapulmonary involvement.
Methods: Prospective, multicentric, and observational study conducted during May 2021-September 2021, included 200 Covid-19 cases with dengue NS1 or Dengue IgM positive, with lung involvement documented and categorized on HRCT thorax at entry point. All cases were subjected to dengue IgG antibody titers and dengue IgM/IgG antibody titer analysis after 12 weeks of discharge form hospital after clinical recovery. Statistical analysis is done by using Chi square test. Results: Dengue-Covid-19 overlap was documented in 16.33% (49/300) cases. CT severity has documented significant correlation with Dengue-Covid-19 overlap cases. [p<0.00001] Hematological parameters as white blood cell count & platelet count were having significant association with Dengue-Covid-19 overlap [p<0.0076] & [p<0.00001] respectively. Clinical parameters as hypoxia have significant association with dengue-covid-19 overlap. [p<0.00001] Inflammatory markers as IL-6, CRP and LDH has significant association in dengue-covid-19 overlap [p<0.00001] respectively. In study of 49 cases of ‘Dengue-covid-19’, post covid lung fibrosis [p<0.004] and serological assessment in dengue IgM/IgG and covid antibody titers has significant association [p<0.00001].
Conclusion: ‘Dengue-covid-19’ is disease of concern in ongoing pandemic in critical care setting, high index of suspicion is must as natural trend of this entity is different and it behaves like ‘two sides of same coin’.